Safety device for



`lan. 8 1924.

Filed 001;. 26. 1922 A III a M f Z 4 Patented Jan. 8, 1924.

'co'.aNEmUs: B.HARDMA1\T, on COLUMBUS, OHIO.

' SAFETY DEVICE FOR IGNITION BIECHAISM.

."Appucationfinaocaiber 2e, 1922. semi no. 596,949.

To all whom t may concern:

Be it known that I, CoRNnLrUs B. HARD` MAN, a citizen of the UnitedStates, residing at Columbus, in the county of Franklin and State ofOhio, have invented certain new and useful Improvements in SafetyDevices for Ignition Mechanism, of which the following is aspecification.

The present invention is directed to im provements in safety devices forignition mechanism, and has for its primary object to provide means toprevent breakage of the magneto controlling arm should the same becomeinaccurately aligned with the tripping arm.

A further object of the invention is to provide a device of thischaracter wherein the tripping arm is equipped with a spring pressedroller capable of yieldably engaging the magneto controlling arm shouldthe lower end of the same be impinged thereagainst during theoscillation thereof.

With these and other objects in view, as will appear as the descriptionproceeds, the invention consists in the novel features of construction,combinations of elements and arrangements of parts, and hereinafter tobe fully described and pointed out in the ap ended claims.

n the accompanying drawing:

Figure 1 is a side elevation of the device,

Figure 2 is an enlarged longitudinal sectional view through the trippingarm, and

Figure 3 is a detail side elevation of the tripping arm showing theroller thereof impinged against the lower end of the magneto controllingarm.

Referring to the drawing 1 designates the timing shaft which is rotatedin the cus tomary manner, said shafthaving fixed thereon an eccentric 2,said shaft being suitably journaled in the engine base 3.

A bracket 4 is supported by the base 3, the arm 5 thereof serving tosupport la mag. neto 6, the oscillating armature shaft thereof havingfixed thereto a controlling arm 8 of the conventional type. Also carriedby the bracket 4 is a bearing 9 -in which is mounted a vertical shaft10, the lower end of which has engaged therein an adjustable bolt11,-the purpose of which will appear later.

The tripping arm 12 has its lower end pivotally connected to the upperend of the "shaft'lO, by apin 13, thel upper end Vof -said arm beingprovided with a longitudinal recess 14 in which is located a coil spring15. This arm is provided with diametrically opposed longitudinal slots16 in which is slidably mounted a roller 17, the same being held againstaccidental displacement b v cotter pins 18 in the ends thereof. The

spring 15l has its upper end engaged with the roller 17 and serves tohold the same yieldably engaged with the upper end walls of said slots,whereby the roller will be normally positioned to strike the arm 8 onalternate sides to rock the same as said arm is oscillated.

In order to oscillate the arm 12 a rod 19 is employed, the forward endof which has secured thereto a head 20, the furcations 21 thereof beingpivotally connected intermediate the ends of the arm 12 by a pin 22. Therear end of the rod 19 is threaded in the extension 23 carried by theband 24 which surrounds the eccentric 2, and since the timing shaft 1 iscontrolled by the engine shaft 22 through the medium of the gears 26 and27, the shaft 19 will be reciprocated as the eccentric is rotated,thereby oscillatingthe tripping arm 12 which in turn rocks the arm 8 ofthe magneto 6.

The bracket 4 carries a bearing 28 in which is rotatably mounted thestem 29 of the cam 30, said stem having fixed therein the forward end ofa rod 31, and since this cam engages the bolt 11 it will be obvious thatthe rod'31 may be rotated to cause the cam to raise or lower the shaft10, and thus the arm 12 to advance or retard the spark, as desired.Since the bolt 11 is adjustable, it is obvious that this bolt may beadjusted to compensate for wear.

Normally the arm 12 strikes the arm 8 near the lower end thereof, firston oneJ side and then on the other to `oscillate the same, butat timeswhen the speed of the engine varies the arm 8 will assume the positionas shown in Figure' 3, and at which time the end thereof will be in suchangular relation with respect to the arm 12 that the army 8 will haveits lower end impinged against the roller 17, and should the arm 12 thenoscillate the arm will break due to the direc-t line of strain impartedthereto. This objection is eliminated by the presence of the spring 15which will permit the roller to yield and move downwardly in the slots18, thereby releasing the arm 8 in an obvious manner.

What is claimed is:

1. In combination with the timing shaft of an internal combustionengine, of a magneto controlling arm, a tripping arm having a yieldablysupported member carried thereby for engaging the magneto arm tooscillate the same, and means for oscillating the tripping arm.

2. In combination with the timing shaft of an internal combustionengine, of a magneto controlling arm, a tripping arm having a rollerslidably and yieldably carried thereby, said roller being adapted toalternately engage the opposite sides of the magneto arm to oscillatethe same, said roller` being capable of sliding downwardly relative thetripping arm when the lower end of the magneto arm is impingedythereagainst, as and for the purpose set forth.

In testimony whereof I atIiX my signature.

CORNELIUS B. HARDMAN.

